What is different about sourcing passives?

Charcroft Electronics’ director, Roger Tall

According to Charcroft Electronics’ director, Roger Tall, continuity of supply for capacitors and resistors needs specialist technical and commercial support.

The component market is seeing a resolution to some of the shortages experienced after 2020 but the picture is not consistent. Some passives have seen a dramatic reduction in minimum lead time, while others are offering lead times which are reduced but still extended.

The picture is mixed even for different types of capacitors/resistors in the same technology. For example, ceramic chip capacitors in larger cases have dropped to one week lead time, while 0201 capacitors remain on allocation. Tantalum capacitors also differ, with some surface-mount polymer dropping significantly, while others remain steady and radial moulded tantalums continue on allocation.

The need for some sectors to use passive components which are qualified or released to the highest levels of reliability can also add to the issues of availability.

So, what can be done to streamline supply for passives on long lead times or allocation? The most important factor is that the distributor delivers specialist passive technical and commercial knowledge, plus the resources to deliver solutions.

A key difference between sourcing a semiconductor and passive is the complexity of the passive’s part number. A capacitor or resistor’s part number is built by combining the different elements in the specification, including value, case size, voltage, termination and tolerance. So, a single family of passive components can have 250 different part numbers. For sectors relying on high levels of reliability, passive part numbers must also show the part has the appropriate qualification or release.

Finding an available alternative for a difficult to source passive starts with considering the full specification of the original design.  Specialist expertise is used to identify a passive which could offer the same parameters on a shorter lead time. For extreme supply issues, it may be possible to justify a different technology option or a complete custom solution.

A UK-manufactured custom passive component or assembly can provide a form-fit-function alternative to fit legacy dimensions and/or provide higher specification by considering modern materials and manufacturing methods.

Some customers are using the specialist commercial support offered by long-term stabilised price agreements to maintain continuity of supply. In these agreements, a stabilised price is agreed with the customer and Charcroft holds UK inventory for the agreement’s duration.

Being a private, independent UK-based distributor gives Charcroft the ability to address global supply issues by offering sourcing solutions which are innovative and developed to support customers’ individual needs.